Replaceable fairing for prosthetic limb or brace

ABSTRACT

A fairing can be attached to a prosthetic limb or over a brace to alter the appearance of the prosthetic limb or brace. The outer surface of the prosthetic limb can be a mirror image of an intact limb and the outer surface of the brace can have an outer surface that corresponds to an injured limb. Because the fairing fits closely around the prosthetic limb or brace, the interior surface of the fairing has a surface that corresponds to a mirror image of an intact limb or an outer surface of an injured limb.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation in part of U.S. patent applicationSer. No. 11/973,069, Prosthetic Limb With Replaceable Fairing filed Oct.5, 2007 which is now U.S. Pat. No. 7,797,072 and a continuation in partof U.S. patent application Ser. No. 12/615,196, Custom Braces, Casts AndDevices And Methods For Designing And Fabricating, filed Nov. 9, 2009.U.S. Pat. No. 7,797,072 and U.S. patent application Ser. No. 12/615,196are hereby incorporated by reference.

BACKGROUND

A prosthesis limb replaces a missing extremity, such as an arm or a legand may be needed for a variety of reasons, including diseases andaccidents. An artificial limb may also be needed when a person is bornwith a missing or damaged limb(s). The type of prosthesis limb used isdetermined largely by the extent of an amputation or loss and locationof the missing limb. A transtibial prosthesis is an artificial leg thatis attached to a user below the knee and includes a lower leg, ankle andfoot. The transfemoral prosthesis is an artificial leg that is attachedto the user's amputated limb above the knee and includes an upper legand mechanical knee. A transradial prosthesis is an artificial arm thatis attached to the user below the elbow and includes a forearm and hand.A transhumeral prosthesis is an artificial arm that is attached to theuser above the elbow.

In developing areas of the world, including large portions of Africa,the leading causes of amputations are industrial, vehicular, and warrelated accidents. In more developed areas, such as North America andEurope, the leading causes for the amputations are diseases includingcancer, infection and circulatory. In the United

States, approximately 100,000 legs are lost each year to diabetes,vascular disorder, accidents and cancer. Because there are so manyamputations, there is a substantial need for prosthetic limbs.

The engineering of prosthetic limbs has improved greatly. In particular,artificial knees and feet have been developed for prosthetic legs thatprovide increased mobility and functionality. While the engineering andmechanics of prosthetic limbs have evolved greatly, very little thoughthas been given to the aesthetics of the human being for whom the devicewas intended. With reference to FIG. 1, a modern prosthetic leg 102 isshown having a socket 122 that has a recessed surface that engages theend of the user's amputated leg. The socket 122 is typically a paddedplastic structure that distributes the compression forces on the end ofthe amputated limb. The bottom of the socket 122 is attached to a pylon124 which is a tubular support that can be made of titanium or aluminum.The pylon can be manufactured through an extrusion process. The bottomof the pylon 124 is attached to an artificial foot 126 that can be amolded plastic structure. The prosthetic leg 102 may also have a foamcovering 128 and can be attached to the socket 122 and pylon 124 toprovide a more uniform shape. The various socket 122, pylon 124 and foot126 can be coupled together using fasteners including bolts, screws andadhesives.

A problem with the existing prosthetics is that they neglect thefundamental symmetry of the human form. Symmetry is a visible indicationof the health of the individual and asymmetry can be perceived as ahealth shortcoming. Many medical conditions such as a nervous tick,stroke, leprosy, elephantitis, etc. are exhibited in patients as anasymmetric appearance. Similarly, the asymmetric nature of existingprosthetic limbs communicates that a user has a ‘medical necessity’ andreinforces a message that the wearer is damaged or defective.

For many amputees the asymmetric appearance of the prosthetic limb ismore troublesome than their physical discomfort. The task of disguisingthe asymmetric appearance of the prosthetic limb is nearly impossiblebecause the socket 121, pylon 123 and foot 125 used to create theprosthetic limb are a collection of parts from a variety ofmanufacturers. Because the socket 121 and pylon 123 are not specificallydesigned for left or right sides of the body, the components cannot havea symmetric appearance. Efforts to improve the appearance with aflesh-colored electrometric foam cover 127 are also problematic. Whilethe diameter of the cross section may be more uniform than the socket121, pylon 123 and foot 125, the cover 127 is not an accuratedimensional representation of a human leg. The simulated human flesh istypically not life like and can connote dead tissue.

Similarly, braces are typically designed to support and protect aninjured limb but not provide any sort of symmetric appearance. There arevarious types of braces that are used to support and protect a portionof a body during recovery. Braces are used to limit the movement of ajoint and are useful in preventing injury or allowing a joint to heal bypreventing movement in the injury direction. Braces can be elastic andmay be made of stretch materials or hinged which include some hardcomponents. Elastic braces are frequently made from woven materials suchas cotton, lycra, nylon or other blends that provide exceptionalbreathability and wearing comfort. These braces conform to the elbow,wrist, leg and knee providing a natural freedom of movement.

What is needed is an improved prosthetic limb and brace that issymmetrical in form and also allows the user to change and personalizethe appearance.

SUMMARY OF THE INVENTION

The present invention is directed towards an improved prosthetic limband brace that can also include a removable fairing that allows the userto personalize and change the appearance of the limb or brace. Theprosthetic limb and fairing are created by a prosthetic designer usingcomputer aided design (CAD) software and computer controlled fabricationprocesses. While the prosthetic limb is described as a leg, the sameprocesses can be used to fabricate prosthetic arms, and as such,prosthetic arms are intended to fall within the scope of the presentinvention. In addition to prosthetic arms, braces including, foot, leg,arm, hand and back braces are intended to fall within the scope of thepresent invention.

The prosthetic designer first creates a virtual limb and fairing using acomputer aided design system. The design of the prosthetic leg caninclude a socket, upper leg, knee, lower leg, and foot. If the user hasan intact leg, a prosthetic leg having a matching outer surface can bedesigned. In order to accurately create a matching prosthetic leg, thesurface of the user's intact leg is first measured. The measurement ofthe intact leg is preferable done with an optical measuring device. In apreferred embodiment a photogrammetry process is used in which thesurface data for a patient is obtained from a plurality of photographsof the patient. In order to accurately measure the surface of thepatient, reference points can be applied to the patient's skin invarious different ways. For example photogrammetry or laser scanning.

In a preferred embodiment a photogrammetry process is used in which thesurface data for a patient is obtained from a plurality of photographsof the patient. In order to accurately measure the surface of thepatient, reference points can be applied to the patient's skin invarious different ways. The surface should have at least twelve welldistributed reference points visible in each photograph and at leasttwenty reference points for an entire surface of an object. Morereference points will result in a more accurate measurement of theobject. The marks can be dots formed by ink, pencil, crayon, grease,graphite, tape, stickers, or other markings placed directly on thepatient or on a form fitting cover such as a stockinette worn by thepatient. In an embodiment, the cloth of the form fitting covering can beprinted with the dots, textured pads or a grid of intersecting lines sothat the patient will have a set of reference points as soon as thecovering is worn by the patient. In yet another embodiment, a lightprojector can be used to project a pattern of light onto the patient.The pattern of light can be an array of spot points, a grid ofintersecting lines or any other pattern that allows images of points onthe patient to be detected. The light on the patient serves as themarkings can be white or colored light markers that are projected ontothe patient with a projector. Multiple projectors or mirrors may benecessary to project the light onto all required surfaces of thepatient.

In addition to reference points for obtaining the surface contours ofthe patient's body surface, the doctor or practitioner can also markareas of the patient's body to indicate the location of other featuresof the brace. For example, markings can indicate the end edge(s) of thebrace, padding areas, boney prominences, sensitive areas of the skin,holes, windows, pathologic sites (fracture or surgical sitelocalization), underlying anatomy (ex spinous processes and spinealignment) recessed areas where the brace should not be made preciselyto the contour of the patient and other features to be formed in thebrace. The markings can be made directly on the patient or on the formfitting cover worn by the patient. Like the reference points, theadditional markings can be ink, ink, pencil, crayon, grease, graphite,tape, stickers, or other markings and must provide a clear visualcontrast. The markings can be coded by color or in another manner toindicate the type of feature to be formed at the markings. The differentcodings can also be used to indicate the degree or amount of deformationin an identified region, type of window, or other brace feature. Themarkings can be a three dimensional object(s) that provide additionalinformation. For example, a rod, an arrow or other object marker canindicate an axis of rotation of a joint or other features.

After the patient has been marked, the portion of the patient's bodythat is in need of a cast or brace is placed in front of one or morestill or video cameras. The cameras can face one or more sides of thepatient's body and can be spaced apart from each other by a knowndistance. In some embodiments, a set of cameras can be arranged aroundthe patient so that a complete set of still images or photographs of thebody around a circumference can be taken. In a preferred embodiment, thecameras are arranged in groups of two cameras. The two cameras can bemounted on a bracket that spaces the cameras apart from each other. Thetwo cameras are aimed in the same general direction towards the patientor limb of the patient but offset by an angle. In a preferredembodiment, the camera lenses can be parallel to each other in a firstplane and angled towards each other in a second plane. The separationand angle allow the two cameras to each take a picture that includes thesame portions of the patient's body but from slightly different angles.The reference points on the body are triangulated from the pictures toobtain the surface contours. If photographs around the entire patientare needed, three or four groups of cameras can be arranged around anddirected towards the patient. The cameras can be coupled to a singleswitch which causes all of the cameras to be actuated simultaneously.The cameras can also be coupled to a flash mechanism. The flash for onecamera can be triggered by the shutter of one camera being actuated. Theother cameras aimed at the patient can include light sensors which causetheir shutters to actuate in response to the flash of light. Thus, theactuation of the first camera will immediately cause all other camerasto be actuated. Since all pictures are taken in a fraction of a second,the body can be placed in front or between the cameras and there isnormally no need to immobilize the patient or hold the body or limbstill for an extended period of time.

This fast image capture feature is particularly important for pediatricor veterinary medical devices such as pediatric spica casts orveterinary braces. It can be very difficult to keep an infant or ananimal steady for other types of scanning processes. For most childrenand animals casting and bracing is a traumatic experience associatedwith significant pain and morbidity. Both application and removal ofcasts and braces is associated with discomfort. For many applicationsthe children and animals require either sedation or anesthesia forapplication of the casts. For example, hip spica casts most frequentlyare applied with the patient in an induced sleep in the operating room.

Capturing a three dimensional image of a child's anatomy requires thatthe child be held immobile during the duration of the scan. Otherwisethe child would require sedation. For most pediatric applications, onlyphotogrammetry will offer near instantaneous three dimensional imagecapture. Combining with markings and photogrammetry, children canundergo virtual fittings for braces while minimizing the need forsedation or anesthesia and reducing the trauma of the experience.Because many infants have a substantial amount of baby fat, the markingof the infant may be the most efficient means for identifying thelocations of the underlying anatomy. Common applications for thistechnology include but are not limited to: pediatric spica casts, Pavlikbrace, clubfoot casting, metartus adductus casting, Blounts diseasecasting/bracing, ankle foot orthosis, pediatric ankle casts, pediatricwalking casts, spine-TLSO braces, halo body cast, cervical collar,torticollis bracing and other medical devices. By obtaining data fromimages, there is no need to keep the infant or animal still for anextended period of time.

In another embodiment, a single 3-D camera can simultaneously capturemultiple off axis images via a single camera. The single camera maycapture multiple images on a single frame of film. The multiple imagescan be used to capture the 3-D image. It is also possible to takemultiple images of a patient with a single camera that is moved aroundthe patient to capture multiple images at different angles if thepatient remains very still. A single camera can also be coupled to alens system that can capture images of the patient from suitable anglesand positions.

In order to get an accurate surface position, each of the referencepoints on the body must be visible in two or more photographs or images.The images are analyzed by a computer surface reconstruction program.The program triangulates the reference points through photogrammetryalso known as digital image correlation to determine a surface geometryof the body. In addition to the reference points, additional features ofthe device as marked on the patient are also shown in the images andvisible to the CAD program operator. The features can include edges ofthe brace or device, holes, pads, windows, hinges, different materialsand other features. The system operator or the CAD software can identifythe features and add the features at the marked locations on the braceor device. Frequently when a brace or cast is needed, the patient issuffering from some internal injuries and additional information such asMRIs or X-rays are available. In an embodiment, the photogrammetry canbe combined with the MRI or X-ray data to identify the locations orregions that need to be accessible or the locations of bones that aresensitive to abrasion. By integrating the MRI and/or X-ray data, thedevice can be made more accurately. The use of data from the othermodalities is especially useful in identifying the axis of rotation ofthe joint accurately in all planes to render a more accurate range ofmotion brace.

In other embodiments, a laser measuring device can be used to scan theintact leg and obtain measurements for surface points across the entireleg that is a digital representation of the outer surface. Laserscanners that are suitable for scanning the leg are available fromPolhemus, HandiScan 3D and Thinglab. Alternatively, the leg can bemeasured through other means. The digital scan data can then beconverted into surface that can be used by the CAD system. This scandata conversion software is available from GeoMagic. A digitalrepresentation of the intact leg surface can then be manipulated by theCAD software to create a mirror image of the intact limb that will beused as the outer surface data for the prosthetic limb. The prostheticdesigner can use the CAD software to join the mirror image surface tothe other components of the prosthetic leg and display the assembledprosthetic leg. Suitable CAD software for prosthetic and fairing designis available from Pro/Engineer. As discussed in the background, foraesthetic and emotional reasons, it is important that the prostheticlimb have a symmetric appearance to the intact leg.

The socket shape must correspond very closely to the end of theamputated limb in order for the prosthetic leg to be comfortable whenworn. The socket design data is typically provided by a prosthetist.Like the leg surface data, the socket design data can be obtainedthrough optical scanning of the end of the amputated limb.Alternatively, the end of the amputated limb can be measured manuallywith various mechanical measuring devices. These measurements are usedto create a socket surface shape that is substantially the reversedshape of the end of the amputated limb. The socket design may alsofactor in padding materials that are placed between the amputated limband the socket wall.

In addition to the mirror image intact limb data and the socket data,the prosthetic leg requires a foot. In an embodiment, feet are stockitems that are manufactured in various sizes and models. Some feet haveenergy-storing members that allow the user to run more efficiently.Alternatively, the feet can be sized to match the intact foot. Digitalrepresentations of the stock feet can be stored in a database that isaccessible to the design system. Alternatively, foot data can beobtained by creating mirror image data of the user's intact foot througha laser scanning process as described above.

The prosthetic designer uses the CAD system to combine the leg surfacedata with socket and foot data to create a complete virtual prostheticleg that is displayed on the computer. The GUI can allow the prostheticleg components to be easily changed using integrated design tools. TheseGUI controls can allow the prosthetic designer to alter the prostheticdesign in various ways. A GUI tool can be used to change the foot usedwith the leg. The GUI tool can also be used to modify the leg to includespecific colors, textures and surface features. Thus, the user cancreate a prosthetic leg that is substantially a mirror image to theintact leg or create a leg that is very different in appearance.

In an embodiment, the prosthetic leg or brace can also include a fairingthat is a removable layer that covers a portion of the prosthetic leg orbrace. The fairings can be removed or replaced so the user can alter theappearance of a portion of the prosthetic leg or brace. The fairing canbe easily changed as desired by the user. The CAD system can also allowthe prosthetic designer to view the prosthetic leg or brace with variousfairing designs. For example, the GUI can include a fairing materialcontroller that allows the user to see many virtual fairings made from avariety of materials including: metals, plastics, fabrics, leather, etc.The prosthetic designer can also use the CAD system to select theattachment mechanism for the fairing. The attachment mechanism caninclude adhesives, fasteners, magnets, etc. The fairing must be securelyattached to the prosthetic leg or brace to remain attached during normalphysical activities. The CAD system is particularly useful because itallows the user to design and view any desired combination of featuresand fairings prior to fabrication.

In addition to the physical appearance, the prosthetic leg or brace mustalso be strong enough for the required use. A prosthetic leg must beable to support the user's weight and impact while running or jumpingand a prosthetic arm must be able to withstand the normal use forces. Inan embodiment, the strength of the prosthetic limb can be provided byinternal structures such as a load-bearing pylon. An outer surface thatis not load bearing can be attached around the load-bearing pylon. Inorder to create a lighter structure, void space can exist between thepylon and the outer surface. In other embodiments, the limb isfabricated with the outer surface functioning as a load-bearing member.Similarly, the brace must provide enough physical strength to properlysupport the injured limb. Because the materials used to fabricate theprosthetic limbs and braces are very strong, the system can design anexternal surface that is a thin wall. The prosthetic limb can possiblyinclude an internal structure that adequately supports the expectedloads and the outer surface wall.

The CAD system can be used to design the load-bearing member of theprosthetic leg. The prosthetic designer can input the weight andactivity level of the user into the CAD system and the required strengthcan then calculate based upon expected loads. The CAD system can thendesign a load-bearing structure that will be able to support the loadrequirements. As discussed above, the load bearing member can be aninternal elongated structure that supports the entire load oralternatively, an integrated design in which the entire structure isload bearing. The CAD system can be used to design a load-bearingstructure that has the required strength for both the internalload-bearing or integrated configurations.

The CAD system can also provide information to the prosthetic designerthat may be important to the prosthetic leg design. For example, theweight of the prosthetic leg will vary depending upon the requiredstrength, the volume of material needed and the density of the material.Once the design is completed, the volume of material and weight can bedetermined. The weight of a fairing can similarly be determined basedupon the volume of the design and materials selected by the user. Thesystem can display the estimated weights for the leg or brace andfairings during the design process. The prosthetic designer candetermine if the weight is suitable for the user. If the weight is tooheavy, the design of the prosthetic leg and fairing may be modified touse lighter weight materials. Ideally, the leg should be as light aspossible while providing the required strength for the user.

In a brace embodiment, the brace can be designed by scanning an injuredlimb and using the surface data to produce a brace having an innersurface that corresponds to the surface data of the injured limb. Thebrace design process is described in U.S. Pat. No. 7,797,072 which isincorporated by reference. Once the design is finalized, the design dataproduced by the CAD system can be used to fabricate the prosthetic legor brace and the fairing. In an embodiment, the prosthetic leg can befabricated as one or more non load-bearing components that surround aninternal load-bearing member that supports the user's weight.Alternatively, the leg can be fabricated as an integrated structurehaving an outer surface that is part of the load-bearing member. Theprosthetic leg can have an exterior shell coupled to an internalframework that can provide additional mechanical strength. The designdata can include a series of cross sections that define outer wall andany internal framework along the length of the prosthetic leg which isused to fabricate the prosthetic leg. In other embodiments, theprosthetic leg or brace can be a completely hollow monocoque design thatas an exterior shell that provides the required load-bearing strength tosupport the expected loads.

In the preferred embodiment, the prosthetic leg and brace are fabricatedthrough a rapid prototyping process that uses an energy beam directed ata bath of material. Similar fabrication processes are known as additivemanufacturing, rapid manufacturing, layered manufacturing, 3D printing,laser sintering, electron beam melting (EBM) and fused materialdeposition (FDM). These fabrication processes use an energy beam that isdeflected across the material and causes the exposed material to harden.

The cross section design data is used by the fabrication machine toconstruct each of the leg or brace components in a sequential series oflayers. As each layer of material is hardened, the completed portion ofthe leg or brace component is moved vertically into the bath and thenext cross section layer is formed and fused to the adjacent formedlayer. When all layers are formed, the prosthetic limb or brace iscompleted. In an embodiment, the lower leg, upper leg, socket, brace andfairings can be fabricated as separate components that are assembled tocreate the prosthetic leg. Since the foot and knee may be off the shelfcomponents, these parts may not need to be fabricated.

The fairing fabrication method will depend upon the selected materialsand design. If the fairing is made of a thin flexible material such asleather, the fairing design data can be used by a computer controlledcutting machine to precisely cut the fairing material to the designshape. Alternatively, the fairing can be fabricated from a flexibleplastic material or sheet metal to form a three dimensional fairing thatcan match the contours of the outer surface of the prosthetic leg orbrace using the rapid prototyping methods described above. The fairingcan be placed around the prosthetic limb or brace and the inner surfaceof the fairing can correspond to a mirror image of the outer surface ofthe intact limb or an outer surface of the injured limb.

It is also possible to combine different fairing components. Forexample, a curved plastic fairing can be covered with a thin flexiblematerial such as leather. Thus, the fairing can be made of both plasticand leather.

Additional processing of the leg components, brace and fairing can beperformed prior to assembly to obtain the desired appearance. Surfacetreatments can include metal plating, painting, covering, texturing,etc. For example, if a metal finish is specified, the components can beplated with a layer of metal using known metal layer depositionprocesses. Additional surface processing can be applied to the metallayer. For example, the metal layer can be brushed, polished, sandblasted, etc.

The prosthetic leg or brace can be assembled once all of the componentsare formed and the surface finishes are applied. The fairing can beattached to the leg or brace with an adhesive or fasteners.Alternatively, the fairing may be clamped around the prosthetic leg orbrace if it is more rigid and the fairing surrounds a portion of the legor brace. The prosthetic leg or brace may also include surface featuresthat function to hold the fairing in place. For example, a recess thatcorresponds to the edge of the fairing can be formed in the outersurface of the prosthetic leg or brace.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be more fully understood by reference to thefollowing detailed description of the invention in conjunction with thedrawings:

FIG. 1 is a view of a prior art prosthetic leg;

FIG. 2 illustrates a patient being marked by a doctor for back bracefabrication;

FIG. 3 illustrates the marked patient being photographed;

FIG. 4 illustrates a top view of a patient being photographed by aplurality of cameras;

FIG. 5 illustrates a computer displaying a digital representation of aportion of the patient;

FIG. 6 illustrates a computer displaying the design process for a backbrace;

FIG. 7 illustrates a basic back brace designed from the digitalrepresentation;

FIG. 8 is a view of a scanning device used to measure an intact leg andan end of an amputated limb;

FIG. 9 is a view of load-bearing components of a prosthetic leg;

FIG. 10 is a view of load-bearing components surrounded by templatesused to design the prosthetic leg;

FIG. 11 is a view of the framework surrounding the load-bearingcomponents trimmed to the desired shape;

FIG. 12 is a view of a fairing placed over the framework of theprosthetic leg;

FIG. 13 is a rear view of a shin fairing;

FIG. 14 is a rear view of the prosthetic leg with the shin fairing inplace and the calf area exposed;

FIG. 15 illustrates a computer screen displaying a prosthetic legdesign;

FIG. 16 is a view of a prosthetic leg having a recessed area;

FIGS. 17 and 18 are views of a prosthetic leg having a nickel finish andan attached leather fairing; and

FIG. 19 illustrates an arm brace with a fairing attached to an outersurface.

DETAILED DESCRIPTION

The present invention is a prosthetic limb having an exterior surfacethat matches the surface contours of a human limb or a brace having aninterior surface that matches the surface contours of a human limb. Theexterior surface can also be modified so a user can alter the appearanceof the prosthetic limb or brace. A replaceable fairing can be designedto cover a portion of the prosthetic limb or brace. The prosthetic limb,or brace and fairing are designed on a computer and the design data canbe used to fabricate the prosthetic leg or brace components usingcomputer controlled fabrication machines. The prosthetic limb or braceis preferably designed by a designer using a Computer Aided design (CAD)program.

The inventive prosthetic leg embodiments include a load-bearingcomponent that functions as the human tibia. The upper end of theload-bearing component is attached to a socket that engages the end ofthe amputated limb and the lower end of the load-bearing component iscoupled to an artificial foot. The foot can be flexible and allow formovement between the load-bearing component and the artificial foot. Thefoot may also include energy storing components that improve thephysical performance of the prosthetic leg when the user is running. Themechanical data for the prosthetic leg that may include the relativepositions of the socket, knee and foot as well as the movement of thesecomponents can be provided by a prosthetist. This mechanical data isinput into a CAD program that is used to design the rest of theprosthetic leg. An example of a suitable CAD program is Pro/Engineer byParametric Technology Corporation. Other CAD software includes:SolidWorks by SolidWorks Corporation a subsidiary of Dassault Systèmes,S. A.

In a preferred embodiment, an exterior surface of the prosthetic leg isa mirror image that is matched to the user's intact leg. Photogrammetryin its broadest sense reverses the photographic process by convertingflat 2-dimensional images of objects back into the real 3-dimensionalobject surface. Two or more different photographs are required toreconstruct a 3-dimensional object. In a perfect photogrammetry process,two photographs would provide enough information to perfectlyreconstruct the 3-dimensional object. Unfortunately, the photography andmeasuring process are generally not perfect so the reconstruction of the3-dimensional object based upon two photos will also have defects. Thephotogrammetry object measurement process can be improved by taking morephotographs and using the extra information to improve the accuracy. Thephotogrammetry process will produce a set of 3-dimensional coordinatesrepresenting a surface of an object from the measurements obtained fromthe multiple photographs.

Photogrammetry uses the principle of triangulation, whereby intersectinglines in space are used to compute the location of a point in all three,XYZ dimensions. In an embodiment, multiple cameras are used tophotograph the leg or body part simultaneously. In order to triangulatea set of points one must also know the camera positions and aimingangles also called the “orientation” for all the pictures in the set. Aprocess called resection does the camera position and aiming anglecalculations for each camera. The cameras should also be calibrated sotheir errors can be defined and removed.

Triangulation is the principle used by photogrammetry to produce3-dimensional point measurements. By mathematically intersectingconverging lines in space, the precise location of the point can bedetermined. Photogrammetry can simultaneously measure multiple pointswith virtually no limit on the number of simultaneously triangulatedpoints. By taking pictures from at least two or more different locationsand measuring the same target in each picture a “line of sight” isdeveloped from each camera location to the target. Since the cameralocations and aiming directions are known, the lines can bemathematically intersected to produce the XYZ coordinates of eachtargeted point.

Resection is the procedure used to determine the coordinates of theobject from photograph data, based upon the camera positions and aimingdirections, also known as the orientation of the camera. Typically, allthe points that are seen and known in XYZ coordinates in the image areused to determine this orientation. For an accurate resection, you mayhave twelve or more well-distributed points in each photograph. If theXYZ coordinates of the points on the object are known, the camera'sorientation can be computed. It is important to realize that both theposition and aiming direction of the camera are needed for resection. Itis not sufficient to know only the camera's position since the cameracould be located in the same place but be aimed in any direction.Consequently, the camera's position which is defined by threecoordinates, and where it is aimed which is defined by three angularcoordinates must be known. Thus, although three values are needed todefine the X, Y and Z coordinates of a target point, six values may berequired to define a point on a picture, XYZ coordinates for position,and XYZ angles for the aiming direction.

The surface being photographed should also have a minimum number ofwell-distributed reference points that appear on each photograph and foran accurate surface measurement. The reference points can be visiblemarks placed on the object that provide a visible contrast that will beclearly shown on the photographs. There should be at least twelvewell-distributed reference points on each photograph and at least twentypoints for the entire surface of the object. The reference points shouldbe evenly distributed on the object and throughout the photograph. Thesurface of the object can be more accurately measured with a largernumber of reference points.

While it is possible to mark the patient's skin with markings, in apreferred embodiment, the patient is covered with a form fittingmaterial such as an elastic cotton tube, stockinette, leotard, bodysuit. In other embodiments, the body can be wrapped with a form fittingmaterial. In another embodiment, the body surface can be sprayed orpainted with removable materials such as a flexible plastic or rubbermaterial that conforms to the body and can marked and easily removedafter images are captured. With reference to FIG. 2, a patient 101 isillustrated wearing a body suit 103 that covers the patient's body, armsand legs. Thus, the markings can be applied to the form fitting materialrather that the patient. The markings can include: ink, pencil, crayon,grease, graphite, tape or any other particles released by a markingdevice. In other embodiments, the markings can include chemical ormagnetic reactions between a pen tip and the material covering thepatient or other markings. The pen tip can be moved over the material tocreate chemical reaction or magnetic material lines that are visible.The markings can also include: adhesive stickers, light points or alight grid projected onto the patient.

In an embodiment, a computer program processes the photographicmeasurements to produce the final XYZ coordinates of all the measuredpoints. In order to do this, the program triangulates the target pointsand resects the pictures. The program may also calibrate the camera.Typical accuracies of the three dimensional measurements can be veryhigh under ideal operating conditions. For example, the measurements canbe accurate to 50-100 microns (0.002″ to 0.004″). However, the accuracyof a photogrammetric measurement can vary significantly since accuracydepends on several inter-related factors. Important accuracy factorsinclude: the resolution and quality of the camera, the size of theobject being measured, the number of photographs taken, and thegeometric layout of the pictures relative to the object and to eachother.

Photogrammetric measurements can be dimensionless. To scale aphotogrammetric measurement, at least one known distance is required.The known distance can be a distance marked on the object. For example,if the actual coordinates for some targeted points are known, thedistances between these points can be determined and the points can beused to scale the measurement. Another possibility is to use a fixturewith targets on it and measure the fixture along with the object.Because the distance between the targets on the fixture is known, it canbe used to scale the other measurements between reference points on theobject. Such fixtures are commonly called scale bars.

In an embodiment, the inventive method is used to make a cast or a bracefor an injured limb. A series of photos are taken of the injured limb.If the bone is broken, fracture should be reduced before the photos aretaken. The photogrammetric processing methods described above are thenused to obtain the surface coordinates of the injured limb. In order todefine common surface points on the limb, reference points can be placedon the limb. The reference points can simply be any contrasting color orreflective points, patterns, shapes, objects, symbols or other opticalindicators which are easily visible. In the preferred embodiment, thereference points are placed and evenly distributed around the entirelimb or portion of the body that the brace is being constructed for.

In addition to the reference points, the patient can also be marked todefine an edge of the brace or other features. With reference to FIG. 2,the doctor can mark the body suit 103 with a pen 105 to define thelocations of the edge of the brace. The edge marking can be one or morecontinuous lines 107 that extend around the body or limb. In otherembodiments, the edge can be defined by a series of marks that definethe edge of the brace and are connected during the brace design.Additional lines 109 can also be marked on the patient to createopenings in the brace. For example, the patient may have injured areasfrom an operation that has been closed with stitches and should not bein contact with the rigid brace. By providing an opening in the brace,the patient's stitches will not be pressed against the brace structure.In FIG. 2, the doctor has drawn a circle around this portion of thepatient's body so that the brace can be designed with a cut out for thisarea. The doctor can also make notes on the body suit 103. The doctorhas written “L6” in ink on the patient to indicate the location of theL6 disk. The doctor has also marked a cross 111 in ink at the greatertrochanter of the femur and dashed lines at the shoulder blades 113.These anatomical locations are important in the design of the brace andare therefore marked on the body suit 103. The marking used to definethe lines, brace edges, holes and annotations can be black or coloredink, pencil, crayon, grease, graphite, tape or any other visible linemarkings. Because photogrammetry uses photographs, the digital pictureswill record all of the lines or other markings.

With reference to FIG. 3, photographs of the patient are taken with aplurality of digital cameras 121. In this example, the cameras 121 aremounted on a bracket 123 and horizontally separated by a known distance.The cameras 121 have the same horizontal position and the lens can be inthe same plane and angled inward towards each other. The angle of thelenses can be between about 5 to 45 degrees. The distances between thepatient 101 and the cameras 121 are also known. The two cameras 121 canbe actuated simultaneously so that the two or more photographs willrepresent the patient 101 in the same position. In order to get the bodycontour information, pictures are taken of the patient 101 wearing themarked body suit 103 from various angles around the entire circumferenceso that all surfaces of the body will be covered by the brace. Eachphotograph should include at least twelve of the reference points. Byprocessing the photographs and triangulating the reference points andother lines and markings in the photographs, the coordinatesrepresenting the body surface can be obtained.

With reference to FIG. 4, a top view of a camera 121 system used tophotograph the patient 101 and body suit 103 is illustrated. In anembodiment, an apparatus that includes a plurality of cameras 121 thatare mounted on brackets 123 and positioned around an open space can beused to photography the patient 101. The cameras 121 are pointed intowards the patient 101 and arranged in groups of two cameras 121. Thecameras 121 can be mounted on brackets 123 that hold the cameras so theyare generally pointing in the same direction but angled slightly towardseach other. The cameras 121 can be positioned with the lenseshorizontally aligned, but rotated slightly about a vertical axis, so thecamera 121 lenses are not parallel. This angle allows the cameras 121 toanalyze the difference in the surfaces so that a 3-dimensionalrepresentation is generated, much as it is with human stereoscopicvision.

In this example, four groups of cameras 121 are mounted around thepatient 101 with each group having two cameras 121. Thus, eight photoseach from different angles are taken of the patient 101. The picturestaken by the cameras 121 together cover the entirety of the torso. Thecamera 121 positions can be moved depending upon the area of interest.In the illustration, the cameras 121 may be configured to collect datafor a back brace. However, if a leg brace is being made, the cameras 121can be lowered to a position around the leg.

An actuator can be coupled to each of the cameras 121 and used to causeall of the cameras to photograph the limb simultaneously. Alternatively,the camera 121 pairs can be synchronized to all take picturessimultaneously to capture the images of the object at the same time.Since the shutter speed is typically just a fraction of a second, thereis no need to keep the patient 101 absolutely still for an extendedperiod of time. In other embodiments, a single camera can be used tocapture multiple images of the patient. In this embodiment, the cameracan capture multiple images simultaneously or in a short period of time.The camera can have multiple lenses each capturing a different image.Alternatively, the patient can move relative to the camera. By rotatingthe patient or rotating the camera about the patient and taking multiplephotographs, a single camera can capture multiple images that can beused to obtain the surface topography and other marker data.

As discussed above, the photographs are processed and used to generatethree dimensional data that accurately describes the outer surface ofthe patient 101. The three dimensional data is then used to design andfabricate the brace or cast. Because the surface data is very accurate,the brace or cast will have a custom fit that accounts for all detectedsurface contours. In addition to the custom fit interior surface, theedges or brace features are also clearly defined by the edge or featuremarkings and can be used to assist in the design of the brace or cast.

In some cases, the physical condition of the patient is such that thephotogrammetry images will not result in an accurate brace. For example,if a patient has injured a limb, the area of injury can be swollen.Thus, any photographs of the limb will result in a scan data that ismuch larger than the unswollen limb. In an embodiment if the patient hasan intact limb that is similar to the damaged limb, the intact limb canbe photographed and the surface data obtained from the intact limb canbe reversed in a mirror manner to create the required data for a bracefor the damaged limb. The brace can be designed and fabricated so thatwhen the swelling goes down, the brace will be ready for the patient.

Photogrammetry also has various benefits over other types of surfacescanning methods including optical and laser scanning because it canalso be used to detect markings placed on the patient by a doctor whichcan be used to indicate special portions of a body or the brace. Forexample, a doctor can draw on the patient to demark any number of notesin ink or other markings on the patient that they will reference laterin the custom device process. These marking may indicate: boundaries ofthe custom prosthetic/orthotic, areas of bony protuberances, folds ofadipose tissue, specific reference vertebrae, sensitive areas on thebody (rashes, birthmarks, moles, etc.) to be avoided, areas that willrequire enhanced ventilation, clearance areas around joints to allowunencumbered motion, setup notes, reference boundaries for ‘shims’ whichwill later add additional pressure within the brace and various otherinformation. The body markings can be colored points, lines or symbols,textured markers, reflective or other codes that are used to identifythe different types of reference points on the patient. For example, apatient may be marked with a first color to indicate a desired boundaryof the brace or cast. The patient can also be marked with a second coloror textured marker to indicate a bony protuberance or sensitive areas.Since the bony protuberances, or underlying bony anatomy are areas proneto skin breakdown, the brace can have special features over these areasto avoid abrasion or damage to these areas. For example, during thedesign process, the operator can reduce the brace over the areas of thepatient's body marked as bony anatomy. An example is the placement ofthe brace over the regions of the scapula. The scapula and its borderscan be palpated manually but are difficult to determine based on surfacemorphology. The brace must accommodate for the scapula to functionproperly. In the techniques the location of the edges or body of thescapula is marked on the patient and the body of the brace willaccommodate the bony edges with custom padding or relief in the bracecontour.

The brace will require pads to be comfortable to the patient. Thelocations of the pads can be marked on the patient as described above.For example, a pad location and shape can be indicated with a codedmarking in the shape of the pad. The CAD system will detect the padmarking and be able to fabricate a pad that matches the designatedshape. During the fabrication process, the pads can be fabricated from asoft elastic material in a range of thicknesses and firmnesses. Forexample, the CAD data can be used to cut the pads from a sheet stock ofpad material. The CAD system can also design the brace to accommodatethe pads. For example, the brace can be designed and fabricated withrecesses formed at the coded and marked areas or other attachmentmechanisms. Since the patient surface data is used to form both thebrace and the pads, they will fit together very accurately. If there areventilation holes designed into the brace over a pad location, the padcan also be designed with ventilation holes that is aligned with theventilation hole in the brace.

When the brace is fitted to the patient, the doctor will have aplurality of pads and will be able to select the best pad thickness forthe patient. Because the brace can be made of a strong and durablematerial, the pads can be worn with use of the brace and may need to bereplaced periodically. The doctor can have additional pads fabricatedfrom the brace data. Additional pads can also be made using additivemanufacturing processes such that the pads have an outer surface that isconforming to the brace and an inner surface that is conforming to thepatient's anatomy in areas with complex surface geometry such as bonyprominences such as the iliac crest.

In other embodiments, the coded marking can be a pattern, symbol, atextured pad, bar code, 3-D objects or other indicators placed or markedon the patient. The coded markings can be black or colored ink, pencil,crayon, grease, graphite, tape or any other visible line markings.Because these cameras use the photographic image for their data input,the coded markings or topography on the patient can be identified by thebrace/cast design software. The inventive process may be able todistinguish different color codings as well as different pad textures.The textures can include grooves, etched patterns, convex or concavesurfaces, etc. Each texture may represent a different feature of thebrace at the marker location. The detection system software mayautomatically detect and identify the coded color or texture. Thesoftware can then automatically design the requested feature of thebrace associated with the coded color or texture was positioned on thepatient. The additional markings will be transferred to the digitalrepresentation of the patient and be used to help design the brace orcast.

The process by which the scanned body data is used to design a brace isillustrated in FIGS. 5-9. FIG. 5 illustrates a scanned image of a humantorso 201 on a CAD screen 221. The contours of the torso 201 areaccurately measured and the additional markings that were placed on thepatient are also illustrated on the scan data. In this example, thedoctor has drawn a cross 211 of the patient's greater trochanter of thefemur so the brace is designed with extra space in this area formovement of the leg. Line markings 208 indicate the desired boundariesof the brace and line 212 indicates a hole in a side of the brace. Thenotation “L6” written in black or colored ink, pencil, crayon, grease,graphite, tape or any other visible markings media is also visible ordetectable from the photogrammetry scan data.

With reference to FIG. 6, the line 208 representing the edge of thebrace is being highlighted. The line 212 representing a hole to beformed in the brace has been highlighted by the brace designer. In thisembodiment, a mouse controlled cursor 215 is used to highlight thelines. In other embodiments, the designer can select click on the lineto highlight the entire line. In this example, the darker linerepresents the portions of the line to be removed from the brace.However, any other visual markings can be used to identify the portionsof the line to be removed.

In some situations, the brace or device may not perfectly match thescanned surface data of the patient. For example, the designer can alsoaccount for the marked cross 211 representing the location of thegreater trochanter of the femur bone. The marking will be indicated onthe images captured during photogrammetry and the cross may be adesignated symbol indicating the location of the greater trochanter. Thesoftware can then adjust the design of the brace over the greatertrochanter by expanding this portion of the brace.

In another example, a patient may have scoliosis and may need acorrective back brace that changes the normal posture of the patient.The brace may be used to correct the curvature of the back to reduce thecurvature deformity. Photographs of the back can be taken to obtain thesurface data as described above. However, the actual spine position maynot be detected unless the surface shows the back bones as surfacefeatures. In order to clearly indicate the spinous processes of theback, the doctor may need to mark the location of each. The marking canbe coded to indentify the specific bones or indicate a bone that isdamaged. The marks can be black or colored ink, pencil, crayon, grease,graphite, tape or any other visible line markings. The markings cansurround the bones, be a cross mark, or any other mark that clearlyidentifies the locations of the bones. When the photogrammetry imagesare processed, the locations of the spinous processes will be clearlyindicated. The back surface and spinous processes locations can then beused to design the back brace.

Rather than designing a back brace that uses the detected spineposition, the back data can be modified to create a brace thatstraightens the patient's back. The designer can obtain measurements forthe overall length and curvature of the spine and the desired curvaturealteration of the brace. The difference between the brace and the normalback position can be specified by the patient's doctor. The designer canthen adjust the recorded back curvature to design a back brace that isstraighter while maintaining the desired interior volume defined by thebrace. In an embodiment, the design program can include a system foradjusting the brace design which allows for the adjustments of one partof the brace to be carried over to the other portions of the brace. Forexample, if the back data shows the photographed spinal curvature, thedesigner can manipulate the apex to reduce the curvature. Rather thanadjusting only the apex portion, the program will make similaradjustments to the surrounding portions of the brace so that thecorrective brace will properly fit the patient. For example, the bracecan be divided into many different thin horizontal sections that mayeach correspond to a different spinous process. When one section ismoved, the other sections will move to a lesser degree so that thescoliotic curvature is reduced. An algorithm may be used to scale themovement of the other sections of the brace on the CAD design. Byautomatically adjusting the different sections of the brace when onesection is moved, the brace design is simplified and accurate.

In other embodiments, the designed brace or cast can vary from thephotogrammetry measurements taken of the patient. For example, thepatient may be swollen due to trauma or inflammation. The brace designsystem can account for the swelling and allow the designer to create asmaller brace that will fit the patient after the swelling is reduced.In an embodiment, the system can use photographs of an intact limb anduse the mirror image surface data as a guide for the brace for theswollen limb. The intact limb may not be a perfect match of the damagedlimb, but in many cases it is sufficiently accurate to form a suitablebrace or cast.

In FIG. 7, the torso is illustrated with the area inside the hole line212 and torso areas outside the edges 208 removed. Although not shown,designer operating the CAD software can rotate the illustrated torso toshow any view of the brace 210. A material thickness can be added to theinterior torso surface to create the basic brace design. Because themarkings are accurately detected by the photogrammetry system, all ofthe marked edge and hole positions are transferred to the digitalrepresentation and the required brace boundaries and features areaccurately identified without having the re-examine or re-measure thepatient. The process completes the basic design of the brace 210.

A similar photogrammetry process can be used to create an externalsurface shape of a prosethetic limb. In other embodiments, the surfacedata of the intact leg can be obtained through a photogrammetry processand input into the CAD program. With reference to FIG. 8, the intact leg205 is photographed by digital cameras 207 from multiple sides to obtaina full three dimensional digital image. The digital cameras 207 create adata set of geometric measurements for many points on the surface of theleg 205. The accuracy and detail of the three dimensional digital imageis improved by taking more photographs of the leg 205. In addition toobtaining data for the intact leg 205, the described photogrammetryprocess can also be used to obtain the surface measurement data for theend of the amputated limb 209. The digital cameras 207 may also be usedto collect color information so that the exact color(s) of the intactleg 205 can be determined and used to create the prosthetic leg. Whilephotogrammetry is the preferred method for determining the surface ofthe intact leg, in other embodiments any other optical, electomagnetic,laser scanning or mechanical method can be used to obtain thisinformation. While some scanning systems are capable of detecting asurface contour with a resolution less than a millimeter, the describedscan does not require this level of accuracy to recreate the appearanceof the intact leg.

The scan data is converted into a usable surface file that can be readby the CAD program. More specifically, the surface data from a scan ofthe intact leg 205 can extrapolate the shape of the intact leg 205through a reconstruction process. The reconstruction process uses analgorithm that connects the adjacent points, known as a point cloud,with lines from the scanned leg data to construct a continuous surfacefrom many small polygon shapes that form a polygon model. The dataproduced by the reconstruction process is a continuous three dimensionaldigital representation that closely matches the surface of the intactleg 205. The same recontruction process can be used to obtain thesurface data for the end of the amputated limb 209. An example of thesoftware used to perform the scanner data reconstruction process isGeomagic Studio by GeoMagic and Pro Scan Tools which is a plug in modulefor Pro/Engineer by Parametric Technology Corporation.

The reconstruction surface file for the intact leg is input into the CADprogram. The prosthetic designer can use the CAD program to reverse andmanipulate the intact leg data to create a mirror image digitalrepresentation. This mirror image data can then be used in the design ofthe exterior surface of the prosthetic leg. The data representing thesurface of the end of the amputated limb 209 can also be manipulated andreversed to create a digital data representing of the interior surfaceof the prosthetic leg socket. It may be necessary to expand this surfaceto allow for some space possibly for padding between the socket and theend of the amputated limb 209.

While the leg and socket data are used to form the outer surfaces of theprosthetic leg, mechanical components are also required for a fullyfunctional design. With reference to FIG. 9, the user can consult with aprosthetist to determine the exact relative placement of the artificialknee 331 and foot 335 in relation to the end of the amputated limb 209.The prosthetist can use the measurement of the intact leg 205 and usethis information as a starting point to determine the relative positionsof the socket, artificial knee 331 and foot 335 in the prosthetic leg.

The knee 331 can be a stock item that includes a multiple linkageassembly that mimics the movement of a human knee. Different knees maybe required for different sized patients and different types of expecteduse. The dimensions and movements of these knees can be stored in acomputer data store. The prosthetist may select the most appropriateknee for the patient and a digital representation of the selected knee331 may be used to accurately design the prosthetic leg.

The artificial foot 335 used with the prosthetic leg can also be a stockitem. Like the artificial knees, digital representations of the variousdifferent types of feet may be available. The proper foot may also beselected for the patient by the prosthetist and the digitalrepresentation can be used in the design of the prosthetic leg. Forexample, the foot 335 shown in FIG. 9 is made of a flexible material toprovide energy storage and cushioning when compression forces areapplied to the heel 341 and toe 343. This type of foot may beparticularly useful for a highly active person who would like to runregularly. Alternatively, the foot or a fairing that is placed over thefoot 335 can be based upon a mirror representation of the user's intactfoot that is created by laser scanning the intact foot as describedabove.

The placement of the artificial knee 331 and foot 335 relative to theend of the amputated limb 209 are specified by the prosthetist and inputinto the CAD program. These components can be displayed within theprosthetic leg on a computer. The CAD program can manipulate thecomponents to enlarge, rotate, add or remove or change components andshow the movement of the prosthetic leg. All internal mechanical designinformation can be saved in computer readable format for futuremodification or prosthetic fabrication.

The internal mechanical component data and mirror image surface data canbe joined together in a virtual prosthetic leg created by the prostheticdesigner with the CAD program. The joining of the surface data and theinternal mechanical components can be done in different ways. In anembodiment, the outer surface is a non load-bearing structure fairingthat is made of a thin material and has the mirror image shape of theintact leg. The fairing is coupled to a series of cross sectiontemplates and longitudinal members that form an internal framework thatare attached to the internal mechanical components. The outer surface isnot load-bearing, so the internal components and outer fairing aredistinct structures. In another embodiment, the outer surface andmechanical components are designed to be an integrated structure withthe outer surface providing part of the load bearing strength.

With reference to FIG. 10, the non load-bearing outer surface embodimentof the prosthetic leg is illustrated. Templates 451 are placed aroundthe internal components in a parallel configuration along the length ofthe leg. Each template 451 extends beyond the exterior surface and eachis trimmed to the corresponding inner surface of the fairing 453. Thefairing 453 is placed around the prosthetic leg (or brace) andintersects each of the templates 451. Because the fairing 453 andtemplates 451 are illustrated in a virtual space, they can pass througheach other during the design phase. The fairing 453 can be substantiallysimilar in both the brace and the prosthetic limb embodiments.

With reference to FIG. 11, the outer surface of the fairing 453 of theprosthetic leg 889 is shown with the fairing 453 removed below the knee331. The templates 451 are cut to remove the portions of the templates451 that extend beyond the inner surface of the fairing 453. Additionallongitudinal members 461 are attached to the templates 451 and extendalong the length of the prosthetic leg 889. The outer edges of thelongitudinal members 461 can also correspond to the inner surface of thefairing. The templates 451 and longitudinal members 461 provide aninternal framework 463 that helps to maintain the shape of the fairing453. The prosthetic designer can alter the templates 451 andlongitudinal members 461 to control the strength of the framework 463.More templates 451 and longitudinal members 461 of a given strength willresult in a stronger framework 463 and prosthetic leg.

In the brace embodiment, the brace can also have templates 451 andlongitudinal members 461 that are attached to the templates 451. Theinterior surfaces of the brace can conform to the exterior shape of theinjured limb.

The prosthetic designer can also design the fairing 453 to be flexiblein areas of the prosthetic leg that move. With reference to FIG. 12, theshin fairing 453 is placed over the frame 463 and foot 335 of theprosthetic leg 889. The non load-bearing fairing 453 may be made of ahigh strength flexible polyamide such as Nylon 6 or 12. In thisembodiment, the fairing 453 wraps around the shin and calf of theprosthetic leg. The fairing 453 also bends with any expected movement ofthe foot 335 and knee 331. As illustrated, the fairing 453 can bedesigned to have a narrow section that only covers the front of the knee331. This thinner fairing width at the knee 331 allows the fairing 453to be more flexible at this area. The fairing 453 may also be designedto only cover the front of the foot 335 which allows for easiermovement. For a close fit, the inner surface of the fairing 453 maymatch the outer surface of the prosthetic leg 889 framework 463. Thus,the inner surface of the fairing 453 can correspond to the outer surfacecontours of the patient's intact limb.

With reference to FIG. 13, the rear portion of the prosthetic leg 889 isillustrated. In this embodiment, the fairing 453 wraps almost fullyaround the upper portion of the prosthetic leg 889 covering the end ofthe amputated limb 206 and socket. The fairing 453 does not cover thecalf portion 671 and the template 451 and longitudinal members 461 thatform the framework 463 are exposed. Like the templates 451, thelongitudinal members 461 may extend from the inner load-bearing memberto the inner surface of the fairing. In other embodiments, theprosthetic designer can extend the fairing 453 around the calf portion671 or add a separate fairing that wraps around the calf portion 671 ofthe prosthetic leg 889.

With reference to FIG. 14, an inner view of a fairing 663 is illustratedthat only covers the shin of the prosthetic leg and does not extendabove the knee. The fairing 663 was designed to flex at the ankle andattach to the foot portion of the prosthetic leg. The thickness of thefairing 663 can be adjusted by the prosthetic designer. Because athinner material is more flexible, the areas that are designed to flexmay be designed with a thinner wall than the sections of the fairing 663that do not move. The fairing can be uniform in thickness and both theinner surface and the outer surface of the fairing 453 can correspond tothe detected outer surface contours of the patient's intact limb.Similarly, if the fairing is used with a brace embodiment, the innersurface and the outer surface of the fairing 453 can correspond to thedetected outer surface contours of the patient's injured limb.

In the previously disclosed embodiments, CAD software has been used tocreate the framework and fairing that are mounted around an internalload-bearing member. In other embodiments, the outer surface of the legis bonded to the internal framework and both function as theload-bearing member. With reference to FIG. 15, a prosthetic leg 987having an external surface 881 that is bonded to an internal frameworkand function together as the load-bearing member is designed using a CADprogram. The prosthetic leg 987 is attached directly to the knee joint983 and the foot joint 985. In this embodiment, the fairing was designedas a separate component that is placed over the outer surface 981 of theprosthetic leg 989 rather than directly over the framework.

In some cases, the user may wish to alter the design of the leg andfairing so that the prosthetic leg is not an exact replica of the intactleg. Similarly, the brace and fairing can be designed to not exactlymatch the injured limb. The user may also want to have multipleinterchangeable fairings for the prosthetic leg. The prosthetic designercan use the CAD software to modify the original design data for thefairing and the leg or brace so the user can create unique personalizeddesigns. Legs, braces and fairings can be designed to have any desiredappearance.

In an embodiment, the CAD system can include a graphical user interface(GUI) that allows the designer to easily change the appearance of theleg, brace and fairing. The GUI can have controls that allow thefairing, brace and leg to be viewed with specific colors, materials,markings and surface features. Within each selected color, theprosthetic designer can also change the appearance by adding coloreffects such as: opaque, translucent, iridescent and metallic. The GUIcan also have controls that allow the leg to be viewed with metal platedsections such as chrome, zinc, gold, silver, nickel and other alloys. AGUI control can also be used to give the surface of the brace orprosthetic leg surface finish. The system can allow the designer to seethe prosthetic leg with a flat, matte, gloss, semi-gloss, reflective,brushed, polished, textured or other finish. These modifications can bemade to the entire fairing and leg or any exposed portions. The user canselect the desired surface appearances that the designer can apply to avirtual brace or leg through the GUI controls. The CAD program willquickly display the virtual brace or prosthetic leg and fairing with allthe desired features. The designer and user can check all of the detailsof the brace or prosthetic design prior to fabrication.

With reference to FIG. 15, an example of a personalized prosthetic leg987 and fairing 991 design is illustrated. In this example, theprosthetic designer has developed a prosthetic leg 987 which ispartially covered with a matte nickel finish 995 that is applied to theouter surface of the leg 987. In this embodiment, the nickel finish 995is applied to the knee joint 983 and the foot joint 985. In addition tobeing ornamental, the smooth nickel finish 995 on the knee joint 983 andthe foot joint 985 can also provide a smooth sliding surface thatimproves the movement of the leg 987. The nickel finish 995 is alsoapplied to the center section of the shin and around the top of the leg987 as an ornamental feature. The prosthetic designer has also used theCAD program to design a black leather fairing 991 that smoothly wrapsaround most of the leg 987. A similar fairing can be applied to a legbrace.

In addition to changing the color and finish of the fairing and surface,the prosthetic designer can also modify the outer surface of theprosthetic limb. With reference to FIG. 16, an example of a surfacemodification is illustrated. In this example, the prosthetic designerhas added a recessed surface 879 in the prosthetic leg 881 that extendsalong a portion of the calf. FIG. 16 illustrates a cross section of theprosthetic leg 881 that shows the recessed surface 879 as a smoothconcave. In other embodiments, the surface of the prosthetic leg can bemodified by the prosthetic designer to extend above the mirror imagesurface.

When the prosthetic designer completes the designs of the prosthetic legand fairing, the design data produced by the CAD software can be used tocustom fabricate the leg and fairing. Rapid prototyping is a generalcategory of systems that uses digital design data and software tofabricate the components from various types of materials includingmetals, plastics and sand. These machines use an energy beam that isdeflected across a bed of liquid or powdered material. The exposure tothe energy beam causes the material to fuse together and harden. Thesefabrication machines are able to create all custom prosthetic limbcomponents.

In order to fabricate the prosthetic leg components with the rapidprototyping machines, the CAD design data must be modified. The normalCAD design data for a component is converted into many parallel crosssections of vector data that extend along the length of the component.The data transmitted between the CAD software and the fabricationmachine approximates the shape of component cross sections through manyconnected triangular facets. Smaller facets produce a higher qualitysurface but require more time to calculate and can create very largermanufacturing data sets.

The vector data for the component cross sections is read by a rapidprototyping scanner controller that converts the vector data to movementinformation which is sent to the energy beam scanhead. In a laser beamembodiment, the rapid prototyping machine includes a scanhead having twomirrors that deflect the laser beam in the X and Y coordinates over abath of material. The fabrication information is then used to controlthe print head cross section to create each component cross sectionsuccessively. The scanhead controller reads the fabrication data andcauses the print head to expose successive layers of liquid, powder, orsheet material to precise patterns of laser light. Once the layer iscompletely formed, the component is moved into the bath so a thin layerof the material covers the previously formed layer. The process isrepeated many times with new layers formed and fused to the previouslyformed layers. In an electron beam embodiment, an eletron beam isdeflected over a bath of material in the X and Y coordinates withmagnetic fields. The component cross sections are sequentially formeduntil the component fabrication is completed.

The primary advantage to additive fabrication rapid prototyping is theability to create very complex shapes and geometric features such as theinternal framework of the templates and longitudinal members within theprosthetic leg. A light weight and strong prosthetic limb can be madewith a rapid prototyping machine from plastic materials such asphotopolymers. FIG. 17 illustrates a completed photopolymer leg 887 thatwas fabricated using a rapid prototyping machine.

The rapid prototyping process can be applied to various materialsincluding thermoplastics, photopolymers, metal powders, eutectic metals,titanium alloys and other materials. Examples of some suitable rapidprototyping machines include: laser sintering machines by EOS GmbH,electron beam sintering machines by A ream AB and laser stereolithography machines by 3D Systems Corp. Similar fabrication processesare known by the names: additive manufacturing, rapid manufacturing,layered manufacturing, 3D printing, laser sintering, electron beammelting (EBM), fused material deposition (FDM), etc. All of thesefabrication process use a similar operating principle of scanning anenergized beam over a bath of material to solidify a precise pattern ofthe material to form each layer until the entire component is complete.

While rapid prototyping is the preferred fabrication method there areother possible methods for forming the prosthetic limb components. In anembodiment, the design information can be used by a computer numericalcontrol (CNC) which controls a machine tool to fabricate components froma solid block of material by the selective removal of material. Acomputer controller reads programing instructions and drives a poweredmechanical cutting tool. The CNC system numerically directsinterpolation of the surface data and controls a cutting tool to createthe component. The CNC process is a sculpting process that is much lessefficient than the rapid prototyping fabrication process and can producea substantial amount of scrap material.

The fairing can also be fabricated using the design data. The mostappropriate fabrication process may depend upon the fairing material.For example, if the fairing is made from a flexible material, thefairing design data can be used to cut the fairing from flat sheetstock. The fairing design data can be used by a computer controlledmachine to precisely cut a sheet of material into the shape of thefairing. The fairing can then be attached directly to a surface of theprosthetic leg with fasteners or an adhesive. If the fairing is made ofa more rigid material, the design data can be used to cut the fairing.The fairing can then be bent or molded to form requiredthree-dimensional shape. It is also possible to fabricate athree-dimensional fairing using the described rapid prototyping process.Like the leg component fabrication method described above, the rapidprototyping machine would use the fairing design data to fabricate thefairing from a sequential series of cross section layers.

Another typical requirement of the prosthetic limb is color. The desiredcolor can also be applied to the prosthetic component, brace or fairingduring the fabrication process. In an embodiment, the color of thefairing, brace and leg components can be applied through pigments thatare mixed with materials used to fabricate the leg. The colors willexist through the structures and cannot be removed. Alternatively, thecolor may be applied to a leg component or brace in a separate painting,dying, deposition or other coloring process to form a color layer overthe outer surfaces of the leg, brace and fairing.

In another embodiment, a metal or ceramic layer can be deposited ontothe outer surfaces of the leg, brace and fairing. The method used todeposit the metal layer can depend upon the base material of the leg,brace or fairing. The metal layer can be deposited on a non-conductiveplastic component through an electroless or chemical plating process. Ifthe component being plated is a conductive material, an electro-chemicalplating process can be used to deposit the metal layer. After the coloror metal layers are applied to the prosthetic components, additionalsurface finishing processes can be performed. Examples of surfacefinishes include flat, matte, gloss, semi-gloss, reflective, brushed,polished and textured that can be applied through known mechanical orchemical processes. A protective clear plastic or paint coating may alsobe applied to the leg, brace and fairing.

The last fabrication step can be attaching the fairings to theprosthetic leg or brace. The fairing can be attached in many differentways. As discussed, in the preferred embodiment, the fairing is aremovable structure that can be easily replaced by the user. Releasablefasteners can be used to hold the fairing to the member. Examples ofreleasable fasteners include bolts, buckles, buttons, clamps, clips,pins, retainers, rivets, bands, snaps, stitching, straps, tacks, ties,zippers, etc. The fairing can also be attached to the leg or brace withan adhesive. In an alternative embodiment, the fairing is permanentlyattached to the leg or brace. Processes that can more permanently attachthe fairing to the leg include: soldering, welding, and fusing.

FIG. 18, illustrates a prosthetic leg 887 after the surfaces have beenmetal plated and the fairing has been attached. The exposed areas of theprosthetic leg 887, the knee joint and ankle joint have a nickel finish895. The nickel finish was applied over the plastic leg using anelectroless nickel-plating process. The fairing 921 was cut from asmooth black leather material and attached to the outer surface of theleg 887 within a recessed area that extends around the shin and calfsections. The leather fairing 921 was attached to the prosthetic leg 887with an adhesive that allows the fairing 921 to be removed and replacedwith another fairing.

With reference to FIG. 19, a substantially similar fairing can beattached over a brace such as an arm brace 901. In an embodiment, theinterior surface of the arm brace 901 corresponds to the surfacetopography of the injured arm 905 that was obtained by the describedphotogrammetry process. The brace 901 can have a uniform thickness.Thus, the outer surface also corresponds to the surface topography ofthe injured arm. A fairing 903 can be placed around the brace 901. Sincethe fairing 903 is designed to fit around the brace 901, the innersurface of the fairing 903 that contacts the brace 901 can have contoursthat match the outer surface of the injured portion of the body. Thefairing 903 can include various different materials such as metals,plastics, leather, etc. as described above. In this example, the fairingcan be marked with a graphical pattern that is either formed withdifferent colors, materials, holes, etc. The fairing 903 can be attachedto the brace 901 with releasable fasteners or an adhesive.

It will be understood that the inventive system has been described withreference to particular embodiments, however additions, deletions andchanges could be made to these embodiments without departing from thescope of the inventive system. For example, the same processes describedfor designing and fabricating a prosthetic leg can also be applied tothe design and construction of a prosthetic arm that can include asocket, an elbow, an elongated member and an artificial hand. Althoughthe prosthetic limb has been described that includes various components,it is well understood that these components and the describedconfiguration can be modified and rearranged in various otherconfigurations.

1. A method for creating a fairing comprising: obtaining surface data for a body; creating fairing fabrication data having an inner surface that corresponds to the surface data for the body; forming a brace for the body; and using the fairing fabrication data to fabricate a fairing, an inner surface of the fairing corresponding to the surface data for the body, the fairing fitting around an outer surface of the brace.
 2. The method of claim 1 further comprising: applying a metal layer to an outer surface of the fairing.
 3. The method of claim 1 further comprising: applying a colored layer to an outer surface of the fairing.
 4. The method of claim 1 further comprising: applying a colored dye to an outer surface of the fairing.
 5. The method of claim 1 further comprising: applying a metal layer to an outer surface of the brace.
 6. The method of claim 1 further comprising: applying a colored layer to an outer surface of the brace.
 7. The method of claim 1 wherein the brace includes a framework having a plurality of openings.
 8. The method of claim 1 wherein the fairing is discontinuous, the fairing covering a first portion of the brace and not covering a second portion of the brace.
 9. The method of claim 1 further comprising: covering a first portion of the brace with the fairing; and leaving a second portion of the brace exposed.
 10. The method of claim 9 wherein the first portion of the brace is an upper surface of the brace and the second portion of the brace is a lower surface of the brace.
 11. The method of claim 9 wherein the first portion of the brace is a front surface of the brace and the second portion of the brace is a side surface of the brace.
 12. The method of claim 1 wherein the brace includes a framework.
 13. The method of claim 1 wherein the fairing includes a metal material.
 14. The method of claim 1 further comprising: performing one or more of the finishing processes on the fairing: plating, texturing, brushing, polishing or sand blasting.
 15. The method of claim 1 further comprising: applying a graphical design to the fairing.
 16. The method of claim 1 wherein the body is a limb.
 17. A method for creating a fairing comprising: obtaining surface data for a body; creating fairing fabrication data having an inner surface that corresponds to the surface data for the body; forming a brace for an injured portion of the body; and using the fairing fabrication data to fabricate multiple interchangeable fairings, inner surfaces of the fairings corresponding to the surface data for the body, the fairings fitting around an outer surface of the brace.
 18. The method of claim 17 wherein the brace includes a plurality of openings.
 19. The method of claim 17 wherein the interchangeable fairings are discontinuous, the interchangeable fairings covering a first portion of the brace and not covering a second portion of the brace.
 20. The method of claim 17 further comprising: covering a first portion of the brace with the interchangeable fairings; and leaving a second portion of the brace exposed. 